early 13c., "an accessory," from Old French ornement "ornament, decoration," and directly from Latin ornamentum "apparatus, equipment, trappings; embellishment, decoration, trinket," from ornare "equip, adorn" (see ornate). Meaning "decoration, embellishment" in English is attested from late 14c. (also a secondary sense in classical Latin). Figurative use from 1550s.

v.

1720, from ornament (n.). Middle English used ournen (late 14c.) in this sense, from Old French orner, from Latin ornare. Related: Ornamented; ornamenting.